Power operated wrench



Oct. 29, 1963 Filed Feb. 14. 1962 v. "K. QuARvE POWER OPERATED WRENCH @DCI H .llrlrrmlw' CL/s Him 11"' Skulmw' 3 Sheets-Sheet 1 FI E. l

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Oct. 29, 1963 v. K. QUARVE 3,103,507

POWER OPERATED WRENCH Filed Feb. 14. 1962 s sheetsheet 2 `mwaNToR [fam/mv @04m/5 BMW@ Arron/ars Oct. 29, 1963 v. K. QUARVE 3,108,507

POWER OPERATED WRENCH Filed Feb, 14, 1962 5 Sheets-Sheet 5 FICE; ,Ev

INVENTOR vo/v A( @weve rrokmsys United States Patent O 3,163,597 PWER OkERATED WRENCH Vernon l. Quarve, Minneapolis, Minn., assigner to Rodgers Hydraulic Incorporated, Minneapolis, Minn., a corporation of Minnesota Filed Feb. 14, 1962, Ser. No. 173,282 3 Qlaims. (Sl. 31-525) The present invention relates to wrenches and more particularly to power operated wrenches of the type supported adjacent to a workpiece and movable by an operator relative to the workpiece as required for performing work in different areas of the workpiece. The invention has particular utility in the assembly and repair of tractor treads.

-In assembling and disassembling various articles of manufacture such as the treads of a tractor, it is 'a common practice to employ a power operated wrench such as an impact wrench. Some of these wrenches must be lifted and moved by hand from one bolt to the next as the work proceeds. Moving such `a wrench by hand can be a very tedious operation because the wrench must be relatively heavy in order to provide the requisite torque.

In certain other devices of the character described, the wrench is supported upon a framework and can be moved with the framework to the position selected for use. Most of these devices have been relatively expensive to construct and cannot be moved easily and quickly from one bolt to the next. Moreover, in many power operated wrenches previously described, there is no provision for precise positioning of the socket end of the wrench so Ias to enable an operator to readily place the wrench socket over a head of a bolt in the event that the bolt is bent or inclined slightly with respect to the surface of the workpiece.

While the invention has general application, it is particularly well adapted for the removal and replacement of the grouser plates of tractor tread. Due to the abrasive nature of the soil in which tractors frequently operate, various parts of the tread rapidly become worn and therefore require relatively frequent replacement or resetting.v

The repair operation is begun by removing the tractor treads from the vehicle. The grouser plates are then removed and the pins and bushings are removed from the rails through the use of a track press of the general type described in my copendin g application Serial No. 716,711, tiled February Z1, 1958, now Patent No. 3,075,346, for Track Press.

Among the problems involved in the repair of tractor treads are the following. The bolts which secure the grouser plates to the rails are often bent or misshapen and in almost every case are frozen or rusted in place. The wrench must therefore berelatively large in size in order to provide the torque required to loosen the bolts. At the same time the wrench must be adapted for easy and rapid movement from one point 4on the tread to another. lt is lalso necessary to provide means enabling the operator to easily place the wrench socket over bolts which are bent or inclined slightly with respect to the upward surface of the tread.

Accordingly it is one important object of the present invention to provide an improved power operated wrench with a support for positioning the wrench above a workpiece and including a means for enabling the wrench to be moved on a path extending normal to a workpiece as well as laterally with respect to the workpiece.

Another important object of the present invention is to provide an improved power operated wrench including a support framework, ya wrench drive unit mounted thereon, and a means for raising and lowering the wrench drive unit relative to the framework to accommodate workpieces of different sizes.

351118,52 iatented Get. 29, 1963 IIt is another important object of the present invention to provide an improved power operated wrench having a framework, an elongate support member, a wrench drive unit mounted at one end of the support member, a drive motor for the wrench at the opposite end thereof to counterbalance the weight of the drive unit, a drive shaft connecting the drive motor `and the wrench, the drive unit being freely movable in all directions with respect to a workpiece.

lt is another object of the present invention to provide an improved power operated wrench wherein the wrench drive mechanism and socket can be easily raised and lowered as well as moved laterally and longitudinally with respect to a workpiece in spite of the relatively large size yand weight of the wrench.

It is yet another object of the present invention to provide an improved power operated wrench assembly having a supporting framework with a wrench drive unit movably mounted thereon, a member for balancing the weight of the wrench drive unit, and a means for quickly and easily moving said wrench and balancing member upwardlyor downwardly upon said framework to thereby adjust the distance of the drive unit above a workpiece.

4it is yet another object of this invention to provide an improved power operated wrench including a rotary impact mechanism, a supporting framework, a drive motor mounted upon the framework to balance the weight of the impact mechanism and the impact mechanism being readily movable to selected positions longitudinally of the workpiece as well as along a path normal to the surface of the workpiece and on a path extending laterally of the workpiece.

These and :other more detailed and specific objects will be disclosed in the course of the following specification, reference being had to the accompanying drawings, in which- FIG. 1 is a side elevational view of one form of the present invention.

FIG. 2 is a plan lview of the apparatus of FIG. l.

PIG. 3 is an end elevational view taken on line 3 3 of PIG. 1.

FIG. 4 is a partial vertical sectional view taken on line 4-4 of FIG. 3.

Referring now to the drawings which illustrate by way of example a preferred form of the present invention, there is shown a power operated wrench including -a supporting framework indicated generally at 10. The supporting framework 16 includes a pair of generally C-shaped tubes 1:2 and 14 secured at their lower ends to a pair of spaced apart horizontally disposed parallel carriage members 16 and 11S. Rotatably mounted at the opposite ends of each of the carriage members 16 and '18 are provided front and rear wheels 20 and 22 respectively. The wheels 2i) and 22 during the operation rest upon a flat `surface or a suitable track such as channels 2d and 26 of roller conveyor 28. The roller conveyor 28 can be suitably supported above the `floor by a plurality of legs 30.

The upper ends of the tubes l2 and 14 are suitably ahixed as by welding to a horizontal support plate 40. Extending vertically from the support plate 4t) and rigidly connected thereto is a post 52. Slidably mounted upon the post i2 is a sleeve or bracket 44 for supporting the power operated wrench drive unit and power unit more fully described hereinbelow.

Extending horizontally from the bracket 44 and rigidly secured thereto is a support shaft 4S best seen in FIG. 3. Rotatably mounted upon shaft 45 is a handwheel 46, a cable 48 or other flexible elongate member is wrapped around a sleeve Si? rigidly secured to the handwheel 46 and is secured to sleeve 50 `at its end. The cable i8` extends upwardly from the bracket and is entrained over a pair of horizontally spaced apart pulleys 52 and 54 which are mounted rotatably at the upper end of the post 42 on parallel horizontally disposed axes. The end of the cable 4S opposite the end secured to the sleeve `551 extends downwardly on the other side of the post 42 and is secured at its end to the bracket 44 at 55. Suitably threaded upon the outward end of the support shaft 4S is a locking nut 57 which can be tightened to lock the handwheel 46 in the desired position.

As can best be seen in FIG. 1, when the handwheel 46 is turned in a counterclockwise direction as viewed in the figures, the cabie 48 will be wound further onto the sleeve 50 of the handwheel 46 thereby shortening the cable loop extending over the pulleys S2 and 54- and as a result causing the bracket 44tto slide upwardly on the post 42. When the handwheel 46 is turned in the opposite direction, bracket 44 will be lowered. The handwheel 46 can be locked in the desired position by tightening the locking nut 57.

Secured to the bracket 44 for pivotal movement with respect to the bracket about a horizontal axis is a mounting piate 59. The mounting plate 59 can be secured to the bracket 44 in any convenient way as for example by a pivot bolt 61. The mounting plate 59 has rigidly secured to it by means of a pair of U bolts 6) and 62 an elongate generally horizontally disposed support member 64 which can be formed for example from metal tubing.

At the right end of the support member 64, as viewed in FIGS. 1 and 2, is a wrench power unit such as an electric motor 66. The electric motor 66 has current supplied to -it through a conductor 68 from a suitable source of current (not shown).

Connected to the left end of the support member 64 as viewed in FIGS. 1 and 2, is a wrench drive unit 72. As best seen in FIGS. 1 and 3, the support member 64 is provided with a generally U-shaped yoke 74 including generally parallel terminal portions 76 and 78. The yoke 74 is preferably pivotally connected to the support member 641 for rotation about the longitudinal axis thereof.

The wrench drive unit 72 includes a generally vertically disposed housing 7 9 mounted within a collar 80 which is tightly secured to the casing 79 by means of bolts S2 and 84. Pivots pins 70 and 71 are screw threaded into opposite sides of the collar 80 and journaled for rotation in the terminal portions 78 and 76 respectively of the yoke 74. The wrench drive unit 72 is therefore able to pivot to a limited extent about a generally horizontal axis transverse of the axis of the support member 64 and is also able to pivot with the yoke 74 about the axis of support member 64, thereby enabling an operator to easily place a socket at the lower end of the wrench onto the head of a bolt even though the bolt is inclined slightly with respect to the surface of the workpiece.

According to the preferred form of my invention, the easing 79 encloses a suitable rotary impact mechanism of known construction which will not be described in detail herein since its construction forms no part of the present invention. In general, any of the heavy duty com mercially available rotary impact mechanisms are satisfactory.

Rotatably mounted within the housing 79 on a vertical axis is a wrench output shaft S6. The lower end of the output shaft 86 extends out of housing 7S and is adapted to receive a suitable socket S3. Any of the various types of sockets commonly employed in heavy duty power operated wrenches can be employed.

At the upper end of housing 79 is provided a reversing transmission 9G. While a suitable reversing transmission of any known construction can be employed, a preferred form of transmission will now be described.

The transmission 90 comprises a hollow casing including suitably connected casing members 92 and 94 and a pair of horizontally spaced apart bearing blocks 96 and d'8 secured within opposite ends thereof. The bearing biocks 3f and 9S are bored eoaxiaily to receive a pinion shaft 11)@ one end of which is rotatably mounted within the bearing block 96 and the other end of which is rotatably mounted within the block 98. Suitable friction reducing ball and roller bearings can be provided between the pinion shaft 160 and the blocks 96 and 9S. Rotatably mounted upon the shaft 160 at opposite ends thereof are a pair of inwardly facing cups 162 and 164.

The cups 162 and 104 include integral sleeve portions 106 and 108 respectively upon which bevel gears 11) and 112 respectively are rotatably mounted. The inward surfaces of the cups 102 and 194 are provided with circumferentially spaced apart axially extending grooves 114 positioned to receive radially extending fingers on alternate clutch plates of clutch assemblies 116 and 117 respectively. The clutch plates between those with the outwardly extending fingers are provided with inwardly extending iingers at their centers which project into axially extending circumferentially spaced apart grooves 118 in the shaft 10G.

Rotatably mounted upon the shaft between the clutch plates 116 and 117 is a sleeve 120. Extending around the outside of the sleeve 121) is a circumferential groove 122 and in the groove 122 is loosely fitted a control collar 124. Collar K1241 is aixed to a control rod 126 which, as can be seen in FIGS. 1, 2 and 4, extends outwardly of the one end of the casing member 92 and is pivotally mounted at 12S upon a crank 130. The crank 130 is affixed to the upper end of a transmission control lever 132 which is itself mounted for rotation on a vertical axis in a suitable support member 134 afiixed to the end of the transmission 96. As can be clearly seen in FIGS. 1 and 2, the shaft 100 is aligned parallel to the support member 64 and the inward end thereof is provided with a shaft connector 136 of any known construction to which is secured one end of a flexible drive shaft 138. The opposite end of drive shaft 138 is suitably secured by shaft connector 149 to an output shaft 142 of the electric motor 66. A gear 113 is mounted upon a transmission output shaft within the casing member 94 for rotation about a vertical axis. The teeth of the gear 113 are positioned in driving engagement with the teeth of gears 119 and 112. The lower end of shaft 115 is suitably coupled to the impact mechanism within the housing 79. The gear 113 can be aiiixed to the shaft 115 by means of a suitable shear pin 119. Friction reducing bearings can be provided between the casing 95 and the gear 113 as well as between the casing and the shaft 115.

During operation, the electric motor 66 will rotate the drive shaft 138 and pinion shaft 1116 thereby causing the continuous rotation of the clutch plates 116 and 117 having inwardly directed fingers which project into the grooves 118. When the transmission control lever 132 is moved in a clockwise direction as viewed in FIG. 2, the control member 126 will move to the left as viewed in FIG. 4. The sleeve iwill also move to the left thereby causing engagement of the clutch plates 116 which in turn will cause the bevel gear 110` to rotate with the shaft y Under these conditions the clutch plates 117 will be disengaged and the bevel gear 112 will idle. The gear 113 and shaft 115 will then rotate in a first direction. When the control lever 132 is moved in the opposite direction the clutch plates 117 will be forced into engagement and the bevel gear 11.2 will then rotate with the shaft 166 thereby causing rotation of the bevel gear 113 and shaft 115 in the opposite direction.

While the apparatus described hereinabove can be employed to perform work on many different types of workpieces, the invention has proved to be particularly valuable in tightening and loosening bolts of tractor treads. Thus a tractor tread designated generally at 131 can be positioned upon the rollers of the conveyor 28 to extend in a horizontal plane beneath the power driven wrench. Tractor tread 131 can comprise a plurality of longitudinally extending rails or links 133 coupled together by means of alternate pins and bushings. Secured to the top of the rails 133 by means of bolts such asv bolts 135 of FIG. 3 are a plurality of grouser plates 137.

In the repair of such treads, the treads 131 are first removed from a vehicle and placed on the conveyor 28 with the grouser plates 137 directed upwardly and the rails 135 Anesting against the upper surface of the rollers of the conveyor 28. Fllhrough the use of the handwheel 46 the bracket 44 and support member 64 can be moved upwardly and downwardly to position the wrench mechanism 72 when it is exactly balanced by the electric motor 66 four to six inches above the bolts 135. The motor 66 can the-n be turned on and the control lever 132 moved in th-e appropriate direction -to turn the output shaft 86 and socket 8S in the appropriate direction to remove the bol-ts 135. After the bolts have been removed, the grouser plates 137 can then be lifted off vfrom the rails and the treads can be further processed according to well known prior practice as described, for example, in my copending application referred to hereinabove.

After the treads have been repaired and reassembled, the grouser plates can be placed back in position and the bolts 135` replaced by means of the improved impact wrench according to this invention, the control lever 132 in this case being turned in a direction to turn shaft 115 and socket 8S in the appropriate direction for tightening the bolts 13S.

Several machines embodying the present invention have been built and used over extended periods of time for repairing tractor track. They proved to be rugged in construction and reliable in operation. While an electric drive motor 66 has been employed, an internal combustion engine can be used in its place, if desired, an-d when this change is made, no outside source of power is required. It was also found that the drive unit 7-2 and socket 88 could be easily and quickly moved from one bolt Ito the next in an arc extending laterally of the workpiece as well as in a vertical arc and when necessary, the operator could easily swing the socket 88 in an arc about the axis of pivot pins 70 and 71 or about the axis of support 64 thus enabling the socket 88 to be quickly placed on a bolt 135` which was inclined slightly with respect to the vertical. The wrench drive unit 72 and motor 66 could also be moved longitudinally of the workpiece when necessary by moving the carriage longitudinally rela-tive to the conveyor 28.

It is understood that suitable modifications may be made in the structure as disclosed, provided such modifications come within the spirit and scope of the appended claims. Having now therefore fully illustrated and described my invention, what I claim to be new and desire to protect by Letters Patent is:

1. A power operated wrench for performing work on an elongated workpiece comprising in combination, a support frame-work, said support framework being movable longitudinally of said workpiece, a portion of said framework extending upwardly above said workpiece, a hori- 5 zontally disposed elongate support member universally connected to said upwardly extending portion, said support member being freely -movable about said universal connection, means for selectively raising and lowering said elongate member on said framework, a drive motor mounted at one end of said elongate support member, an impacting means universally mounted at the opposite end of said support member, said impacting mechanism being freely pivotab-le in all ydirections with respect to said support member, a drive shaft rotatably mounted within said impacting mechanism for rota-tion about a vertical axis, the lower Iend of said drive shaft bei-ng adapted to receive a socket thereon and a drive means operatively connecting said drive motor and said impacting mechanism to impact rotary movement thereto.

2. The apparatus according to claim 1 wherein a selectively operable reversing transmission is connected between said impacting mechanism and said drive moto-r.

3. A power operated impact Wrench for performing work on a tractor tread, said apparatus comprising in combination, a supporting frame, said frame being movable longitudinally of said tractor tread, a bracket member mounted on the upper end of said supporting frame above said tractor tread, means for raising and lowering said bracket upon said frame, a horizontally disposed elongate member mounted upon said bracket for pivotal movement about a lhorizontal axis transverse of said elongate member, a drive motor -mounted at one end of said elongate member, an impacting means mounted at the opposite end of said elongate member, said impacting means including a housing and a drive shaft rotatably mounted therein for rotation about a vertical axis, the lower end of said drive shaft being adapted to receive a socket thereon, said housing lbeing mounted at the end of said elongate member for pivotal movement about a horizontal axis with respect to said elongate mem-ber, a selectively operable reversing transmission operatively connected to said impacting mechanism and a drive means operatively connected between said drive motor and said transmission.

References Cited in the le of this patent UNITED STATES PATENTS y 1,320,375 Brown Nov. 4, 1919 1,322,391 Alexander Nov.A 18, 1919 1,734,475 Dedge Nov. 5, 1929 2,037,701 Bronander Apr. 2l, 1936 2,086,261 Douglass July 6, 1937 2,316,747 Stephens Apr. 13, 1943 2,585,113 Gredell Feb. l2, 1952 2,597,337 Kershaw May 20, 19512 2,645,964 Kochaver July 21, 1953 2,872,835 Talkington Feb. 10, 1959 2,017,794 Pouget Jan. 23, 1962 FOREIGN PATENTS F.A.l7,437 France June 2l, 1913 

1. A POWER OPERATED WRENCH FOR PERFORMING WORK ON AN ELONGATED WORKPIECE COMPRISING IN COMBINATION, A SUPPORT FRAMEWORK, SAID SUPPORT FRAMEWORK BEING MOVABLE LONGITUDIANLLY OF SAID WORKPIECE, A PORTION OF SAID FRAMEWORK EXTENDING UPWARDLY ABOVE SAID WORKPIECE, A HORIZONTALLY DISPOSED ELONGATE SUPPORT MEMBER UNIVERSALLY CONNECTED TO SAID UPWARDLY EXTENDING PORTION, SAID SUPPORT MEMBER BEING FREELY MOVABLE ABOUT SAID UNIVERSAL CONNECTION, MEANS FOR SELECTIVELY RAISING AND LOWERING SAID ELONGATE MEMBER ON SAID FRAMEWORK, A DRIVE MOTOR MOUNTED AT ONE END OF SAID ELONGATE SUPPORT MEMBER, AN IMPACTING MEANS UNIVERSALLY MOUNTED AT THE OPPOSITE END OF SAID SUPPORT MEMBER, SAID IMPACTING MECHANISM BEING FREELY PIVOTABLE IN ALL DIRECTIONS WITH RESPECT TO SAID SUPPORT MEMBER, A DRIVE SHAFT ROTATABLY MOUNTED WITHIN SAID IMPACTING MECHANISM FOR ROTATION ABOUT A VERTICAL AXIS, THE LOWER END OF SAID DRIVE SHAFT BEING ADAPTED TO RECEIVE A SOCKET THEREON AND A DRIVE MEANS OPERATIVELY CONNECTING SAID DRIVE MOTOR AND SAID IMPACTING MECHANISM TO IMPACT ROTARY MOVEMENT THERETO. 